Participants insisted that such offers were authorized under Amendment 64, which allows Colorado adults 21 and over to possess small amounts of marijuana. Law enforcers disagreed -- including, presumably, the folks at the Douglas County Sheriff's Office, who've busted Andrew Walton for taking part in such a scheme.

Here are a couple examples of Craigslist giveaways we shared in a February 4 post. This ad, entitled "Fresh and Cured Hash," included numerous photos, including this one....

...and text touting "$60 gram for BHO and $40g for Full melt." However, the items are not for sale. "I ask donations for my time, energy, the ability to grow the plant, then make oils, the cost of butane and ice for hash," it reads. Another section announces that the deal is "Amendment 64 & 20 compliant."

Another ad, headlined "Donate today and receive free MJ with free delivery!," struck a similar theme. Underneath this photo....

...was copy that referenced one of A64's main proponents. It read:

Mason Tvert once said, "There's no doubt that if people choose to use marijuana instead of alcohol we would not have the same number of problems."

We agree 100%. That is why we are now accepting supporting donations which go to support marijuana law reform and as a gesture of our gratitude you will receive free marijuana (amount received depends on amount donated)....

Donate $30 and receive a free 1/8!

Donate $60 and receive a free 1/4!

We are fully Amendment 64 compliant! You absolutely MUST be 21 years of age or older and have valid government-issued identification!

We also spoke to the folks at 4 Strains Pipe & Tobacco , who offered a free gram on a $30 purchase of pipes or other items for sale in the shop. They told us they'd consulted an attorney, who assured them that their approach was perfectly legal under Amendment 64. But another lawyer we spoke with disagreed -- and so did the authorities.

Continue for more about marijuana giveaways and the arrest of Andrew Walton.

When we asked marijuana attorney and advocate Warren Edson about marijuana giveaways, he was mighty dubious.

Warren Edson.

"Remuneration is more than just money," he told us. "And in these situations, can you really say marijuana is free if you have to do something else to get it? If I can walk into a head shop and say, 'Can I have a gram of buds?,' and they'll give it to me, that's one thing. That's a game the medical marijuana world played, with people giving away stuff left and right until the Medical Marijuana Enforcement Division said you can't give away stuff below cost. And if I can't just walk in and get some capacity without having to buy other stuff, that's not free."

This message was reinforced at a Denver City Council meeting by Denver police chief Robert White. When asked about such deals, he laughed as he replied, "It is illegal, and we are investigating as we speak."

Colorado Attorney General John Suthers echoed this thought process, telling CBS4 that these offers were a "scam" and "indicative of some of the stuff that's going on to work around the letter of the law."

As publicity about so-called free pot rose, some would-be entrepreneurs got cold feet. For instance, we wrote about a company called Legal Chronic Delivery, which promised to bring customers weed at no charge if they donated $50 for this bumper sticker:

Shortly after our post went live, though, the site disappeared.

Andrew Walton didn't, and he may now become a test case for whether these services are kosher or not.

According to the DCSO, detectives with the Douglas County Pattern Crime Unit came across a Craigslist ad offering to deliver marijuana to any location for a donation. They responded by reaching out and requesting a delivery to a location in Lone Tree. A short time later, Walton arrived. But rather than receiving said donation, he was cuffed, and the pot he had in his possession -- three-and-a-half ounces worth -- was confiscated. He's now been charged with unlawful distribution of marijuana of less than five pounds with a prior conviction.

Walton subsequently posted a $1,500 bond and was released. Meanwhile, the DCSO offers this message:

Note: Amendment 64 authorizes possession of marijuana. However, there is no law authorizing the distribution or sale of marijuana (except medical marijuana).